JPS5948901B2 - Automatic transmission shift point control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for controlling shift points during upshifts and downshifts of an automatic transmission.

An automatic transmission usually includes a shift valve, and automatically changes gears by upshifting and downshifting by operating the shift valve.

A shift valve typically has throttle pressure (or line pressure) applied to its spool, and governor pressure applied to the spool in opposition to this pressure and a spring, causing the spool to respond to these pressures, thereby causing the accelerator pedal to be pressed all at once. (If the engine throttle opening is 778, for example)
(equivalent to an accelerator operation range that is less than the throttle opening) is configured to change the upshift and downshift shift points during partial according to the throttle opening and vehicle speed.

On the other hand, the shift valve applies kickdown pressure to the spool when the accelerator pedal is fully depressed (corresponding to the accelerator operation range where the engine throttle opening is, for example, 7/8 or more). The system is also configured to perform a downshift operation based on the governor pressure, and then perform an upshift operation based on the governor pressure as the vehicle speed increases.

However, in conventional shift valves, the throttle pressure (or line pressure) and kickdown pressure act on the same pressure receiving surface of the spool, so upshift and downshift shift points are determined at partial and kickdown times. They cannot be determined independently, and it has been impossible to make ideal upshift and downshift shift points for both.

In addition, the conventional shift valve prevents the throttle pressure (or line pressure) mentioned above from acting on the spool in the upshift state, and thereby creates hysteresis in the shift pattern during downshifts. We are trying to change the shift pattern as desired depending on the time, but in this case, the shift pattern during downshifting is unique due to the area of action of the spool's throttle pressure (or line pressure), which is also a determining factor in the shift pattern during upshifting. Therefore, if the shift pattern at the time of upshifting is set to the ideal one, the shift 1 to pattern at the time of downshifting will deviate from the ideal one.

The present invention applies Scot 1 health pressure (or line pressure) and kickdown pressure to separate spool pressure receiving surfaces of the shift valve, and applies kickdown pressure to separate spool receiving pressures at the downshift position and upshift position. The shift valve has been improved so that it acts on the surface, and the spool is divided into two in the axial direction, one for oil passage switching and one for control, and when downshifting, a relatively high throttle pressure or line is applied to the divided end of the spool. A downshift valve is provided that supplies pressure to force the shift valve to downshift independently of its own downshift operation, so that the shift pattern for upshifting during partial is set by the shift valve, and the shift pattern for upshifting during partial If the shift patterns for downshifts can be determined by the downshift valves, the upshift and downshift shift points during partial and the upshift I and downshift shift points during kickdown can be determined without any correlation. , can be individually determined to be the ideal one, and from the viewpoint that the problems of the conventional shift valve can be solved all at once, we would like to provide a shift point control device for an automatic transmission that embodies this idea. That is.

The present invention further provides for maintaining the oil passage switching spool at a downshift position by applying hydraulic pressure related to the fixed forward gear range to the split end face of the spool of the shift valve, thereby securing the range. Therefore, the present invention also proposes a shift point control device for an automatic transmission that can eliminate the conventionally necessary lock valve from the automatic transmission.

Hereinafter, the present invention will be explained based on the attached figures.

Figure 1 shows the structure of the internal power transmission parts of an automatic transmission with three forward speeds and one reverse speed, including crank shirts 1 to 100 driven by the engine, a torque converter 101, an input shaft 102, and a front Clutch 104, rear clutch 105, second brake 106, low and reverse brake 107
, one-way clutch 108, intermediate shirt l~109
, first planetary gear group 110, second planetary gear group 111 . output shaft 112, first governor valve 113,
It is composed of a second governor valve 114 and an oil pump 115.

The torque converter 100 consists of a pump impeller P, a turbine runner T, and a stator S. The pump impeller P is driven by a crankshaft 100 and is fixed to an input shaft 102 to rotate the torque converter hydraulic oil contained therein. Apply torque to the turbine runner T.

Torque is further transmitted to the transmission gear train by input shaft 102.

Stator S is placed on sleeve 116 via one-way clutch 103.

The one-way clutch 103 has a structure that allows the stator S to rotate in the same direction as the crankshaft 100, that is, in the direction of the arrow (hereinafter referred to as normal rotation), but does not allow rotation in the opposite direction (hereinafter referred to as reverse rotation). .

The first planetary gear group 110 includes an internal gear 117 fixed to an intermediate shaft 109, a sun gear 119 fixed to a hollow transmission shaft 118, and an internal gear 117.
and two or more planet pinions 120 that can rotate and revolve simultaneously while meshing with each of the sun gears 119, and a front planet carrier 121 that is fixed to the output shaft 112 and supports the planet pinions 120. 2 planetary gear group 11
1 is an internal gear 122 fixed to the output shaft 112, a sun gear 123 fixed to the hollow transmission shaft 118, and 2 which can rotate and revolve simultaneously while meshing with each of the internal gear 122 and the sun gear 123. More than 124 planet pinions
, a rear planet carrier 125 supporting the planet pinion 124.

A front clutch 104 is connected to an input shaft 102 driven by a turbine runner T and both sun gears 1.
19, 123 and a hollow transmission shaft 118 that rotates integrally with each other via a drum 126, and the rear clutch 105 connects the input shaft 102 and the internal gear of the first planetary gear group 110 via an intermediate shaft 109. 117.

The second brake 106 is constructed by winding and tightening a drum 126 fixed to a hollow conduction shaft 118.
Fix both sun gears 119 and 123, and
The reverse brake 107 moves to fix the rear planet carrier 125 of the second planetary gear group 111.

The one-way clutch 108 has a structure that allows the rear planet carrier 125 to rotate in the normal direction, but not in the reverse direction.

A first governor valve 113 and a second governor valve 114 are fixed to the output shaft 112 and generate governor pressure according to the vehicle speed.

Next, the power transmission train when the select lever is set to the D (forward automatic transmission) position will be explained.

In this case, only the rear clutch 105, which is the forward input clutch, is initially engaged.

The power that passes through the torque converter 101 from the engine is
From the input shaft 102 through the rear clutch 105 to the internal gear 11 of the first planetary gear group 110
7.

Internal gear 117 rotates planet gear 120 in the normal direction.

Therefore, the sun gear 119 rotates in reverse, and the planet gear 124 of the second planetary gear group 111 rotates in the normal direction in order to reverse the sun gear 123 of the second planetary gear group 111, which rotates together with the sun gear 119. .

One-way clutch 108 prevents sun gear 123 from reversing rear planet carrier 125 and acts as a forward reaction brake.

Therefore, the internal gear 1 of the second planetary gear group 111
22 rotates normally.

Therefore, the output shaft 112, which rotates integrally with the internal gear 122, also rotates in the normal direction, and the reduction ratio of the first forward speed is obtained.

In this state, the vehicle speed increases and the second brake
6 is engaged, the power from the input shaft 102 passing through the rear clutch 105 is transmitted to the internal gear 117 as in the case of the first speed.

Second brake 106 fixes drum 126, prevents rotation of sun gear 119, and functions as a forward reaction brake.

Therefore, the planet pinion 120 revolves around the stationary sun gear 119 while rotating, and therefore the front planet carrier 121 and the output shaft 112 integrated therewith are decelerated, but the first It rotates forward at a faster speed than in the case of high speed, and the reduction ratio of the second forward speed is obtained, and the vehicle speed further increases and the second speed
When the brake 106 is released and the front clutch 104 is engaged, one side of the power transmitted to the input shaft 102 is transmitted to the internal gear 117 via the rear clutch 105, and the other side is transmitted to the front clutch 1.
04 and is transmitted to the sun gear 119.

Therefore, the internal gear 117 and the sun gear 119 are interlocked, and together with the front planet carrier 121 and the output shaft 112, they all rotate normally at the same rotational speed to obtain the third forward speed.

In this case, the input clutches are the front clutch 104 and the rear clutch 105, and since torque is not increased by the planetary gear, there is no reaction brake.

Next, the power transmission train when the select lever is set to the R (reverse travel) position will be explained.

In this case, the front clutch 104 and the low and
Reverse brake 107 is engaged.

Power from the engine passes through the torque converter 101 and is transferred from the input shaft 102 to the front clutch 104.
, through the drum 126 to the sun gears 119 and 123.

At this time, the rear planet carrier 125 is
Since it is fixed by the reverse brake 107, when the sun gears 119 and 123 rotate forward, the internal gear 122 is decelerated and reversed, and the output shaft 1 rotates integrally with the internal gear 122.
12 is also reversed to obtain a reverse reduction ratio.

Fig. 2 shows a hydraulic system in which the shift point control device of the present invention is installed in the shift control circuit of the automatic transmission described above, with regulator valve 1, manual valve 2.1-2 shift valve 3, and improved according to the present invention. 2-3 shift valve 4, 3-2 downshift valve 5, line pressure booster valve 6, pressure modifier valve 7, throttle valve 8, throttle fail-safe valve 9, throttle modulator valve 10 constituting a part of the device of the present invention .1 speed fixed range pressure reducing valve 11. Accumulator 12.2-
3 timing valve 13.3-2 timing valve 14
, a front clutch pressure reducing valve 15, a torque converter 101, a rear clutch 105, a band servo 106' for operating and inactivating the second brake 106 (see FIG. 1), a low and reverse brake 107, and a governor valve. 113, 114, and an oil pump 115 through the illustrated circuit network, the shift point control device of the present invention has a 2-3 shift valve 4 and a 3-2 downshift valve 5 as main components.

The oil pump 115 is driven by the engine via the crankshaft 100 and the pump impeller P of the torque converter 101, and while the engine is running, oil is constantly pumped from a reservoir (not shown) through an oil strainer (not shown) from which harmful contaminants have been removed. It is sucked up and sent to the line pressure circuit 16.

A regulator valve 1 for adjusting the oil to a predetermined pressure includes a spool 1b which is urged by a spring 1a to the raised position shown in the left half of the figure and is slidably fitted into a housing 1C. It has separate chambers 1d, le, 1f, and Ig.

The oil pressure in the line pressure circuit 16 is connected to the oil passage 1 in the chambers 1d and If.
It is supplied via 7 and 18.

Further, the chamber 1j above the plug 11 is connected to the chamber 1g below the spool 1b through an oil passage 54.

Line pressure is supplied to the chamber 1e from the port 2b of the manual valve 2 through the oil passage 22 when in the D range, II range, or ■ range, which will be described later.

The run lb' of the spool 1b has a slightly smaller diameter than the corresponding protrusion 1c' of the housing 1C, and a minute gap is set between the two that acts as a variable orifice.

Through this gap, oil within 1f is constantly drawn out from drain port 1h at a speed determined by the amount of overlap between land lb' and protrusion 1c', and the oil in line pressure circuit 16 is drawn out in proportion to this amount of overlap. can generate high line pressure.

Also, the land 1b'' of the spool 1b is made slightly smaller than the hole 10'' of the housing 1C to create a small gap between the two, and through this gap, the oil in the chamber 1f is routed from the oil passage 19 to the torque converter 101 and the oil cooler. , 20 and various lubricating parts 21 in the transmission.

The line pressure of the line pressure circuit 16 is sent to the manual valve 2, and this manual valve selectively switches the line pressure circuit 16 to ports 2a, 2b, 2C, 2
The spool 2f is slidably fitted into the housing 2e.

Six positions are set for spool 2f: neutral (N), forward automatic transmission (D), 2nd speed fixed (I), 1st speed fixed (I), reverse (R), and parking (P). When the spool 2f is moved to each range by the above selection operation, the line pressure circuit 16 communicates with the ports marked with ○ in the table below.

Note that all ports that do not communicate with the line pressure circuit 16 communicate with openings on both sides of the housing 2e and serve as drain ports.

First governor valve 113 and second governor valve 11
4 generates governor pressure corresponding to the vehicle speed while driving forward, and as is clear from the table above, manual valve 2 is set to D.
, II and ■, line pressure circuit 1
Line pressure is first sent to the second governor valve 114 from port 2b (which connects to port 6) through the circuit 22, and when the car is running, the line pressure is regulated by the second governor valve 114 to adjust according to the vehicle speed. A governor pressure is generated, and this governor pressure is the first
Governor valve 113 is reached.

When the vehicle speed exceeds a predetermined value, the first governor valve 1
13 begins to output to the governor pressure circuit 23 to which it was led.

This governor pressure is supplied from the circuit 23 to the 1=2 shift valve 3.
2-3 shift valve 4 and 3-2 downshift valve 5
and control the operation of these valves as described below.

The 1-2 shift valve 3 is constructed by fitting two spools 3b and 3C coaxially and slidably abuttingly into a housing 3a.

A spring 3d is applied to the end face of the spool 3b that is far from the spool 3C, so that the end face of the spool 3C that is far from the spool 3b faces the chamber 3e.

Lands 3f, 3g, 3 with larger diameters are placed on the spool 3b in sequence.
h, and protrusions 31, 3j, 3 corresponding to these lands.
k is formed in the housing 3a.

The spool 3C is provided with a land 31.3m and lands 3n and 30 with a larger diameter than these lands, two protrusions 3p and 3q for the land 31, and a protrusion 3 for the land 3m.
r is formed in the housing 3a.

1-2 The shift valve 3 is connected to the governor pressure circuit 2 as shown in the diagram.
3. Connect the kickdown pressure circuit 24 and the shift control pressure circuit 25, and further connect the oil path 27 which communicates with the oil path 26 or drain port 3S depending on the position of the land 31.

The governor pressure circuit 23 is connected to the chamber 3e, and the kickdown pressure circuit 24 is connected to the run 3g when the spool 3b is in the right half of the figure.
, 3b, and when the spool 3b is in the left half of the figure, it communicates between the lands 3g and 3b and between the lands 3f and 3g.

Further, the speed change control pressure circuit 25 communicates between the lands 3m and 3n when the spool 3C is in the right half of the drawing, and is cut off at the land 3n when the spool 3C is in the left half of the drawing.

The oil passage 26 is connected to the output port of the shuttle valve 28,
Oil passage 27 is connected to low and reverse brake 107.

The 1-2 shift valve 3 is further connected to an oil passage 30 extending from an oil passage 29 that branches from the middle of the oil passage 22 facing the governor valves 113, 114 from the port 2b of the manual valve 2 and reaches the rear clutch 105. , an oil passage 31 that communicates with or is blocked from the oil passage 30 depending on the position of the land 3h is connected and provided between the 1-2 shift valve 3 and the 2-3 shift valve 4.

Note that the oil passage 31 communicates with the drain port 3t when the spool 3C is in the position shown in the right half of the figure.

An orifice 74 and a check valve 7 are located in the middle of the oil passage 29.
7 in parallel.

The 2-3 shift valve 4 is constructed by fitting two spools 4b and 4C coaxially and slidably abuttingly into a housing 4a.

A spring 4d is applied to the end face of the spool 4b far from the spool 4C, the end face of the spool 4C far from the spool 4b faces the chamber 4e, and a spring 4f is applied between the spools 4b and 4C.
to be reduced.

Lands 4g and 4h with sequentially larger diameters on spool 4b
, 4i, and protrusions 4j corresponding to these lands,
4, 41 is formed on the housing 4a.

Two lands 4m and 4n are formed on the spool 4C, and an oil passage 32 is connected to the 2-3 shift valve 4, which communicates with or is blocked from the oil passage 31 having an orifice 73 in the middle depending on the position of the land 4m. do.

The oil passage 32 communicates with the drain port 4r when the spool 4C is located in the right half of the figure.

A chamber 40 formed between both spools 4b and 4C is connected to an output port of a shuttle valve 34 through an oil passage 33.

This shuttle valve has one input port connected to the port 2C of the manual valve 2 through an oil passage 35, and the other input port connected to an oil passage 36.

The chamber 4e is connected to the governor pressure circuit 23, and the chamber 4p housing the spring 4a is connected to the kickdown pressure circuit 24 through an oil passage 37.

The kickdown pressure circuit 24 is connected to the upper pressure receiving surface of the land 4g when the spool 4b is in the right half of the figure, and to both the upper and lower pressure receiving surfaces of the land 4g and the land 4h when the spool 4b is in the left half of the figure. The kickdown pressure is applied to the upper pressure receiving surface.

The 2-3 shift valve 4 is further supplied with shift control pressure via an oil passage 38 so that shift control pressure can be applied between the land 4h and the land 41 when the valve block 4b is located in the right half of the figure. In addition to connecting the circuit 25, a drain port 4q is provided which communicates between the land 4h and the land 41 when the spool 4b is located in the left half of the figure.

3-2 The downshift valve 5 is constructed by slidably fitting a spool 5b into a housing 5a.

A spring 5C is applied to one end surface of the spool 5b, and the other end surface is made to face the chamber 5d.

3-2 The oil passage 36 is connected to the downshift valve 5 so as to communicate with the oil passage 39 extending from the shift control pressure circuit 25 or the drain port 5f depending on the position of the land 5e of the spool 5b, is connected to the governor pressure circuit 23.

The line pressure starter valve 6 includes a spool 6b slidably fitted into a housing 6a.
is biased to the left in the figure by a spring 6c.

The spool 6b has grooves 6d and 6e, and the groove 6e is connected to the chamber 6.
It has an oil passage 6g that leads to f.

This line pressure booster valve 6 has an oil passage 40 that communicates with the groove 6e when the spool 6b moves to the left, and a groove 6e when the spool 6b moves to the right.
The oil passage 41 that leads to is connected.

The oil passage 40 merges with the oil passage 32 and leads to the 2-3 timing valve 13 and the front clutch pressure reduction valve 15,
The oil passage 41 is connected to the oil passage 31, and these oil passages are connected to the servo apply chamber 1 of the band servo 106' by an oil passage 42.
Connect to 06'a.

The line pressure booster valve 6 is further connected with an oil passage 43 which is always in communication with the groove 6d, and an oil passage 44 which is selectively communicated with the oil passage 43 via the groove 6d depending on the position of the spool 6b. 45 is connected, and the oil passage 43 is connected to the shuttle valve 4.
6, the oil passage 44 is connected to the throttle fail-safe valve 9 via an oil passage 47 in a chamber 6h housing a spring 6C, and the oil passage 45 is connected to the port 2C of the manual valve 2, respectively.

The throttle valve 8 is fitted inside the housing 8a.

- A plunger 8d is coaxially disposed opposite to the spool via a spring 8C.

The plunger 8d is linked to the accelerator pedal via a linkage, etc., and when the accelerator pedal is depressed, it is pushed from the idle position shown in the upper half of the figure to the right side of the figure, and the spring 8C
The spring force can be increased.

The spool 8b has a groove 8e, and the throttle pressure circuit 48 and oil passage 49 are connected to the throttle valve 8 so as to be in continuous communication with this groove.

The throttle valve 8 further includes a drain port 8f communicating with the throttle pressure circuit 48 via a groove 8e and an oil passage 50 from the line pressure circuit 16, depending on the position of the spool 8b.
is opened and the oil passage 49 is communicated with the chamber 8g.

When the plunger 8d is moved to the right by pressing the accelerator pedal and the spring force of the spring 8c is increased, the chamber 8q
Throttle pressure created by draining part of the line pressure from the oil passage 50 to the drain port 8f is output to the throttle pressure circuit 48 so that the oil pressure inside balances the spring force.

Thus, the throttle valve 8 outputs a throttle pressure proportional to the throttle opening corresponding to the spring force of the spring 8C (accelerator pedal depression amount) by adjusting the line pressure.

Furthermore, when you press the accelerator pedal to the kick town position,
The plunger 8d completely bends the spring 8C and the spool 8
b and pushes the spool 8b to the limit to shut off the drain port 8f and open the throttle pressure circuit 48.
is connected to the oil passage 50, and the throttle pressure becomes the same value as the line pressure.

The throttle pressure circuit 48 is connected to the other input port 1 of the shutoff valve 46 and leads to the throttle failsafe valve 9 via an oil passage 51.

The throttle fail-safe valve 9 includes a sleeve 9a slidably fitted in the housing 8a thereof so as to guide the plunger 8d of the throttle valve 8, and the leftward movement of this sleeve is elastically restrained by a spring 9b.

The oil passage 47 connecting the line pressure booster valve 6 and the throttle failsafe valve 9 normally communicates with the drain port 9C of the throttle failsafe valve 9.

The oil passage 51 communicates with the chamber 9d housing the spring 9b on one side, and the chamber 9f facing the enlarged portion 8j of the plunger 8d via the port 1-9e on the other hand, and the kickdown pressure circuit 24 communicates with the port 9g.

Further, an oil passage 52 branched from the line pressure circuit 16 is led to the throttle fail-safe valve 9, and this oil passage is normally shut off, but as will be explained later, the sleeve 9a
In the event of an abnormality in which the oil passage is located in the left half position in the figure, it is possible to communicate with the oil passage 47.

Thus, during the pushing of the plunger 8d, the throttle pressure in the throttle pressure circuit 48 is reduced to the oil passage 51. It passes through the port 9e to the chamber 9f, acts on the enlarged portion 8j of the plunger 8d, imparts a force in the pushing direction to the plunger 8d, and causes the spring 8C to
By facing the accelerator pedal, the pressing force of the accelerator pedal becomes spring 8C.
This can prevent it from becoming heavier.

Furthermore, when the plunger 8d is pushed into the kickdown position, the kickdown pressure circuit 24, which had been connected to the drain port 8h via the port 9g, is cut off from the drain port 8h, and the ports 9e, 9e, the chamber 9f, and the port 9g are disconnected from the drain port 8h. It communicates with oil passage 51 via .

At this time, as described above, the spool 8b is pushed to the right in the figure and the line pressure in the oil passage 50 is supplied to the throttle pressure circuit 48 as it is without being drained.
A kickdown pressure equal to the line pressure is output.

This kickdown pressure is also supplied to the throttle modulator valve 10 via the oil passage 53.

By the way, an abnormality occurs in the accelerator cage that links the accelerator pedal and the plunger 8d, and the connection between the plunger 8d and the accelerator pedal becomes disconnected, and a return spring (not shown) causes the plunger 8d to return to the idle position shown in the upper half of the figure or higher. When the sleeve 9a is engaged with the plunger 8d, the sleeve 9a is moved to the left as shown in the lower half of the figure.

At this time, since the spring 8C does not act on the spool 8b,
Open spool 8b (drain port) 8f slightly,
The oil passage 50 is brought into a nearly closed state.

In addition, the oil passage 51 passes through the port 9e and the chamber 9f to the drain ports 1 and 9C to make the throttle pressure zero, while the oil passage 4
7 is connected to the oil passage 52 to guide line pressure to the oil passage 47.
, an oil passage 43, and a shuttle valve 46 to the pressure modifier valve 7, where the pressure is regulated to a magnitude equal to the spring force of the spring 7C when the spool 7b is in the left half in the figure.

This pressure modifier pressure is supplied to the chambers 1g and 1j of the regulator valve 1 through the oil passage 54 at the highest value,
Increase line pressure to maximum value.

As a result, by tightening the friction elements at the highest line pressure, it is possible to drive the vehicle to a repair shop without causing seizure due to slippage of the friction elements.

The pressure modifier valve 7 is constructed by slidably fitting a spool 7b into a housing 7a, and a spring 7C is applied to one end surface of the spool 7b, while the other end surface faces the chamber 7d.

A groove 7e is formed on the spool 7b, and an output capo 7f, a drain port 7g, and an input capo 7h, which always face the groove, are formed on the housing 7a.

Ports) 7g and 7h are arranged in such a position that when one port starts to open while the spool 7b is moving, the other port finishes closing, and port) 7f is connected to one chamber 7d by an oil passage 54.
On the other hand, the chamber 1g of the regulator valve 1 and the spool 1b
The plugs 11 provided opposite to each other are connected to the facing chambers 1j, and the ports 7h are connected to the output port of the shuttle valve 46.

Thus, the pressure modifier valve 7 is
The hydraulic pressure input to h is the setting force of spring 7C (spool 7
Spring force of spring 7C when b is in the left half position in the figure)
When it is smaller, the spool 7b is positioned below the left half position in the figure by the spring 7C to block the drain port 7g and connect the port 7f to the port 7h, so that the input port 7h is not connected to the port 7h. The oil pressure remains at port 7f.
The oil is supplied to the regulator valve 1 through the oil passage 54.

During this time, this oil pressure is also guided to the chamber 7d, and as the oil pressure rises, the spool 7b is pushed from the position shown in the right half of the figure to the position shown in the left half by the spring force of the spring 7C. let

However, as the oil pressure output from the port 7f rises more than that, the spool 7b rises further from the position shown in the left half of the figure and connects the port 7f to the drain port 7g, causing the oil passage 54 to flow. The output hydraulic pressure is from spool 7.
When b is in the position shown in the left half of the figure, the pressure modifier pressure cannot exceed the magnitude determined by the spring force of the spring 7C.

The throttle modulator valve 10 includes a housing 10
In a, there are three lands 10b, 1oc.

A spool 10e having a diameter of 10d is slidably fitted, and a spring 10g whose spring force can be adjusted by an adjuster 10f acts on one end surface of the spool 10e, and the other end surface faces a chamber 10h.

A circuit 25 is connected to the housing 10a so as to constantly communicate with the groove between the land 10b and the IOC of the spool 10e, and the oil passage 56 extending from the oil passage 53 and the port 2b of the manual valve 2 is connected to one oil passage while the spool 10e is moving. housing 1 so that when the oil passage starts to open, the other oil passage finishes closing.
Connect to 0a.

An oil passage 57 is further connected to the housing 10a at a location corresponding to the connection portion of the circuit 25, and the oil passage 57 is filled in the chamber 10i in which the spring 10g is housed.

Further, the chamber 10h communicates with the throttle valve 8 through an oil passage 49.

This throttle modulator valve 10 has an oil passage 49
When the throttle pressure introduced into the chamber 10h is zero, the spool 10e is placed in the position shown in the lower half of the figure by the spring 10g.

At this time, the oil passage 56 from the manual valve 2 is cut off from the circuit 25 and the oil passage 57 at the spool 10b, and the shift control pressure circuit 25 and the oil passage 57 are connected to the oil passage 53 and the port 9g of the throttle fail-safe valve 9. The drain port 8h is connected to the drain port 8h, and no oil pressure is generated in the circuit 25 and the oil passage 57.

As the throttle pressure increases, the spool 10e is moved by the spring 10.
When the line pressure is guided from the port 2b of the manual valve 2 to the oil passage 56, this line pressure is introduced to the chamber 10i via the oil passage 57. The spool 10e is pushed back to the upper half position in the figure in cooperation with the spring 10g, and is balanced in this position.

Thus, the throttle modulator valve 10 is connected to the oil passage 5.
While controlling the line pressure from 6 by the throttle pressure guided within 10 hours, the throttle modulator pressure rises from, for example, 2/4 throttle opening, and thereafter outputs to the shift control pressure circuit 25 a throttle modulator pressure that is approximately proportional to the throttle opening. can do.

In addition, in the kickdown state when the plunger 8d of the throttle valve 8 is pushed in, the port 9g is cut off from the drain port 8h as described above, and the throttle pressure equivalent to the line pressure is applied from the port 9g via the oil passage 53 to the throttle modulator valve. 10, the shift control pressure circuit 25
A pressure equivalent to the line pressure is output to the oil passage 57, and this pressure reaches the chamber 10i and spools 10e.
2 to the left in the figure to the limit position, a pressure equivalent to the line pressure is constantly output to the circuit 25 in the kickdown state.

The first speed fixed range pressure reducing valve 11 includes a spool 11b slidably fitted into a housing 11a, and a spring 11C is applied to one end surface of the spool 11b, and a chamber 11d is applied to the other end surface.
Let's face it.

A groove 11e is formed in the spool 11b, and an oil passage 58 is connected to the housing 11a so as to constantly communicate with this groove, and the oil passage 58 is communicated with one input port of the shuttle valve 28 and the chamber 11d.

The housing 11a is further provided with a drain port 11f, and an oil passage 5 from the port 2d of the manual valve 2.
The drain port Ilf and the oil passage 59 are arranged so that when one starts to open while the spool Ilb is moving, the other finishes closing.

Therefore, the first speed fixed range pressure reducing valve 11 drains a part of the line pressure output from the manual valve 2 to the oil passage 59 to the drain port 11f to reduce the pressure when the range is selected. A low and reverse brake 1 which is also used when reversing by outputting a certain amount of reduced pressure oil to the oil passage 58 determined by the spring force when the brake is in the position of
07 from becoming too large in capacity.

The port 2a of the manual valve 2 is connected to the other input port of the shuttle valve 28 by an oil passage 60, and
An orifice 78 and a check valve 79 are inserted in parallel in the middle of the oil passage 60 which is connected to one input port of the shuttle valve 61 and communicates the output port of this shuttle valve with the front clutch LO4 through an oil passage 62. The upstream side is branched to communicate with the chamber 12a of the accumulator 12.

This accumulator is composed of a stepped piston 12b and a stepped cylinder 12C fitted with the stepped piston 12b.
In addition to the chamber 12a, two chambers 112d and 12e are defined, and a spring 12f urges the piston 12b upward in the figure.

The chamber 12d communicates with the oil passage 29 through an oil passage 63, and the chamber 12e communicates with the oil passage 42 through an oil passage 64, respectively.

An orifice 75 and a check valve 76 are inserted in parallel on the upstream side of the oil passage 42 by the accumulator 12.

2-3 The timing valve 13 includes a spool 13b slidably fitted into a housing 13a, and has a spring 13C acting on one end surface thereof, and the other end surface faces a chamber 13d, and the chamber 13d is connected to an oil passage 40. Make it understandable.

The spool 13b has a spring 13C that causes the oil passage 65 to connect to the drain port H3e in the lowered position shown in the right half of the figure, and to connect the oil passage 65 to the oil passage 40 via 13d in the raised position shown in the left half of the figure. shall be made.

The 3-2 timing valve 14 includes a spool 14b slidably fitted in a housing 14a, with a spring 14C acting on one end surface and the other end facing the chamber 14d.

The spool 14b responds to the governor pressure guided from the governor pressure circuit 23 to the chamber 14d via the oil passage 66, and when the spool 14b is in the lowered position shown in the right half of the figure, the oil passage 65
is the servo release chamber 106b' of the band servo 106'.
It is assumed that the oil passage 65 is in communication with the oil passage 67 leading to the oil passage 67, and is cut off from the oil passage 67 when the oil passage 65 is in the raised position shown in the left half of the figure.

Also between oil lines 65 and 67. 3-2 timing valve 14
A parallel circuit 80 consisting of the check valve 68 and the orifice 69 is inserted by bypassing.

The front clutch pressure reducing valve 15 has a spool 15b slidably fitted into a housing 15a.

A spring 15C is applied to one end surface thereof, and the other end surface faces the chamber 15d.

A groove 15e is formed on the spool 15b, lands are set on both sides of the groove 15e, and a land 1 having a larger diameter than these lands is formed.
Provide 5f.

An oil passage 7 is provided in the housing 15a so as to constantly communicate with the groove 15e.
0 and connect this oil passage to the other input port of the shuttle valve 61.

A drain port 15g is further formed in the housing 15a, and an oil passage 40 is connected thereto, and these are connected to the spool 15b.
While moving, arrange them so that when one begins to open, the other finishes closing.

Further, an oil passage 71 is connected to the housing 15a at a location opposite to the oil passage 70, and this oil passage is communicated with the chamber 15d.
A chamber 15h containing 5C is connected to the throttle pressure circuit 48 through an oil passage 72.

In the front clutch pressure reducing valve 15, the spool 15b is normally moved to the lowered position shown in the right half of the figure by the spring 15C, so that the oil passage 70 is cut off from the drain port 15g and communicated with the oil passage 40.

Therefore, a 2-3 shuttle valve 4, which will be described later, is installed in the oil passage 40.
When the line pressure is led through the oil passages 31 and 32 under the action of the oil passage 70 and the shuttle valve 6
1 and is led to the front clutch 104.

However, since this line pressure is throttled by the orifice 73 in the oil passage 31, it is initially low and then gradually rises.

This pressure is also led to the chamber 15d via the oil passage 71, and pushes the spool 15b upward in the figure.

On the other hand, an oil passage 72 is connected to the chamber 15h from the throttle pressure circuit 48.
Throttle pressure proportional to the throttle opening is supplied through , and this throttle pressure cooperates with the spring 15C to push down the spool 15b downward in the figure, to a position where this pushing down force and the above pushing up force are balanced. The spool 15b remains there.

By the way, when the supply pressure to the front clutch 104 reaches a certain value after rising, the spool 15b is raised to the left half position in the figure, the oil passage 70 is disconnected from the oil passage 40, and the drain is closed. It now communicates with port 15g and is balanced at the left half position in the figure.

Therefore, the front clutch supply pressure cannot exceed the above-mentioned certain value.

However, since the throttle pressure is led to the chamber 15h and is involved in controlling the front clutch supply pressure, the front clutch supply pressure increases as the throttle opening increases.

Note that in the kickdown state, the throttle pressure increases to the line pressure as described above, so the front clutch supply pressure also changes accordingly.

The operation of the speed change control circuit including the device of the present invention constructed as described above will now be described.

First, the regulator valve 1 has the pump pressure from the oil pump 115 in the chamber 1d, the pressure modifier pressure from the pressure modifier valve 7 in the chamber 1j, and the chamber 1j only when in the D range, II range, or ■ range. Line pressure from port 2b of manual valve 2 is led to chamber 1e, applying downward force to spool 1b in the figure, and pressure modifier pressure is led to chamber 1g, causing spool 1b to It is pushed upward in the figure by the spring force of spring 1a.

Thus, by keeping the spool 1b in a position where these forces are balanced, a line pressure determined by this spool position can be created in the circuit 16, and this line pressure is transferred from the circuit 16 to the corresponding manual valve 2. It is always guided by the port.

In addition, in the P range, R range, and N range, the chamber 1e of the regulator valve 1 is drained through the port 2b of the manual valve 2, so that the regulator valve 1 moves the spool 1b downward with the line pressure of the chamber 1e. Since no pushing force is generated, the line pressure of the circuit 16 is increased compared to the D range, II range, and ■ range.

Here, the driver moves manual valve 2 from N range to D.
When in range, line pressure circuit 16 leads to port 2b, from which line pressure passes through oil passage 56 to throttle modulator valve 10 on the one hand, and to oil passage 22 on the other hand.
, 29 and is supplied to the rear clutch 105.

The line pressure supplied to the throttle modulator valve 10 via the oil passage 56 is regulated to the throttle modulator pressure by this valve, and is output from the oil passage 25.

The line pressure passing through the oil passage 29 is throttled by the orifice 74 on the way to the rear clutch 105, and is initially low and then gradually rising as it is supplied to the rear clutch 105.

This rear clutch supply pressure also reaches the accumulator chamber 12d via the oil passage 63, and pushes down the stepped piston 12b toward the larger diameter side against the spring 12f.

As a result, the rear clutch supply pressure is slowly increased, and the rear clutch 105 is slowly engaged without causing the select shock when the manual valve 2 is changed from the N range to the D range. The transmission becomes ready to start in first gear.

Further, the line pressure discharged from the port 2b of the manual valve 2 to the oil passage 22 is also guided to the governor valves 113 and 114, and these governor valves output governor pressure corresponding to the vehicle speed to the circuit 23 as described above.

This governor pressure is applied to the port 2b of the manual valve 2 in forward travel ranges D and II as described above.

Since all of (1) communicate with the line pressure circuit 16 and lead the line pressure to the oil passage 22, it is constantly output to the governor pressure circuit 23 while the manual valve 2 is in the forward travel range.

After the vehicle starts, the vehicle speed reaches a value, and the governor pressure corresponding to this vehicle speed that reaches the chamber 3e of the 1-2 shift valve 3 from the circuit 23 is applied to the spools 3b and 3 located in the right half position in the figure.
When C overcomes the downward force by the spring 3d and the downward force generated by the throttle modulator pressure from the circuit 25 acting on the difference in pressure receiving area between the lands 3m and 3n, the spool 3b
, 3C rise from the right half position in the figure.

During this time, if the land 3m comes off the protrusion 3r, the land 3
The chamber between m and 3n leads to drain port) 3S, and the throttle modulator pressure from circuit 25 acts on the area difference between lands 3m and 3n, and the force that was pushing spool 3C downward disappears, causing spools 3b and 3C to move instantly. and rises to the left half position in the figure.

As a result, the oil passage 30 branched from the oil passage 29 becomes the oil passage 31.
The line pressure led to the oil passage 29 as described above is output to the oil passage 31 via the oil passage 30.1-2 and the shift valve 3.

This line pressure is then supplied to the servo apply chamber 106a' through the oil passage 42, but on the way it passes through the orifice 75.
As a result, the servo apply pressure is initially low and then gradually rises.

This servo apply pressure also reaches the accumulator chamber 12e through the oil passage 64, and pushes back the stepped piston 12b, which is in the lowered position as described above, in cooperation with the spring 12f.

As a result, the servo blithe pressure slowly rises, and the band servo 106' slowly operates the second brake 106.

Due to the operation of the second brake, the automatic transmission is shifted up from the first speed to the second speed together with the engagement of the clutch 105. This can be alleviated by

When the vehicle speed further increases while running in second gear, the governor pressure that corresponds to this vehicle speed and reaches the chamber 4e of the 2-3 shift valve 4 from the circuit 23 is increased by the spool 4b located in the right half position in the figure.
, 4C, the downward force due to spring 4d, and circuit 25.38
The throttle modulator pressure from the land 4h overcomes the downward force generated due to the difference in pressure receiving area between the land 4h and the land 41, and raises the spools 4b and 4C from the right half position in the figure.

During this time, if the land 4h comes off the protrusion 4k, the land 4h
, 4d communicate with the drain port 4q, the downward force due to the throttle modulator pressure disappears, and the spools 4b, 4C instantly rise to the left half position in the figure.

As a result, the oil passage 32 communicates with the oil passage 31, and the line pressure that was led to the oil passage 31 as described above is output to the oil passage 40 via the 2-3 shift valve 4 and the oil passage 32.

This line pressure is applied from the oil passage 40 to the chamber 6f via the passages 6e and 6g of the line pressure booster valve 6, and moves the spool 6b from the upper half position to the lower half position in the figure against the spring 6C. On the other hand, it is guided to the chamber 13d of the 2-3 timing valve 13 and the corresponding port of the front clutch pressure reducing valve 15.

By the way, since the line pressure guided to the oil passage 40 is restricted by the orifice 73 provided in the middle of the oil passage 31, it is initially low and then gradually rises.

Therefore, the hydraulic pressure led to the chamber 13d from the oil passage 40 cannot initially raise the spool 13b against the spring 13C, and the spool 13b is in the right half position in the figure, and the oil passage 40
The pressure led to the chamber 15d of the front clutch pressure reducing valve 15 via the oil passage 71 initially acts on the spool 15b due to the downward force caused by the spring 15C and the throttle pressure that reaches the chamber 15h from the throttle pressure circuit 48 via the oil passage 72. It is not possible to overcome the downward force caused by this force and raise it from the right half position in the figure.

Therefore, the pressure supplied from the oil passage 40 to the chamber 13d stops here, and the pressure supplied from the oil passage 40 to the front clutch pressure reducing valve 15 passes through the oil passage 70 and the shuttle valve 61 as it is, and then continues through the oil passage 62. It is then supplied to the front clutch 104.

After that, the pressure inside the oil passage 40 rises, and this causes the spool 1
5b is raised to the left half position in the figure, the front clutch 104 is not supplied with the line pressure itself, but with this pressure reduced as described above due to the pressure regulating action of the front clutch pressure reducing valve 15, and the throttle of the oil passage 72 is applied. By adjusting the pressure according to the pressure, a pressure that is approximately proportional to the output energy of the engine is supplied.

During this time, the pressure in the oil passage 40 is reduced to 2-3 timing valve 1.
When the pressure rises to a value that overcomes the spring 13C of No. 3, this pressure raises the spool 13b from the right half position to the left half position in the figure, causing the chamber 13d to communicate with the oil passage 65, and from the oil passage 40 into the chamber. The pressure that had reached 13d is output to the oil passage 65.

Thereafter, the pressure is transferred from the oil passage 65 through an oil passage 80 provided with a check valve 68, and then through an oil passage 67 to the servo release chamber 1.
06b'.

When line pressure is supplied to the servo release chamber 106b', the piston of the band servo 106 moves into the servo apply chamber 1.
Since the pressure receiving area of the servo release chamber 106b' is larger than that of the servo release chamber 106a', the piston is placed in the servo apply chamber 1.
It is pushed back to the 06a' side.

As a result of the above action, the pressure supplied to the front clutch 104 exceeds the value and the front clutch starts to be engaged, and then the pressure is supplied to the servo release chamber 106b' (
Second brake 106 by band servo 106b'
The engagement of the front clutch 104 can be made to overlap slightly with the operation of the second brake, thereby preventing the engine from racing by releasing both of them. In conjunction with the aforementioned engagement and holding of the rear clutch 105, the automatic transmission can be shifted up from the second speed to the third speed.

While driving in third gear, when the vehicle speed exceeds a value, the governor pressure from the circuit 23 to the chamber 5d of the 3-2 downshift valve 5 causes the spool 5b of the valve to resist the spring 5C. When the accelerator pedal is pressed to increase the throttle opening while the vehicle is raised to the left half position in the figure,
The throttle modulator pressure that corresponds to this throttle opening and reaches the 3-2 downshift valve 5 via the oil path 39 from the shift control pressure circuit 25 acts on the difference in pressure receiving area between the land 5e and the land 5g, and the spring 5C The spool 5b is pushed down to the right half position in the figure.

As a result, the oil passages 36 and 39 are electrically connected, and the throttle modulator pressure is reduced between the oil passages 39 and 36 and the shuttle valve 34.
It then enters the chamber 4C of the 2-3 shift valve 4, overcomes the governor pressure in the chamber 4e, and pushes the spool 4C down from the left half position in the figure to the right half position.

As a result, the connection between the oil passages 31 and 32 is cut off, and the line pressure supply to the oil passage 32 is cut off. At the same time, the oil passage 32 is connected to the drain port) 4r, and the front clutch 104 and the servo release chamber 106b' are connected to each other in the third speed. The pressure supplied to the is removed as described below.

That is, in order to prevent pressure from being generated in the chamber 15d of the front clutch pressure reducing valve 15, the spool 15b is moved to the right half position in the figure by the spring 15C, and the front clutch pressure is maintained between the oil passages 40 and 70. From there, it is extracted relatively quickly through the oil passage 62, the shuttle valve 61, the oil passages 70, 40, 32, and the drain port (4r).

On the other hand, the servo release pressure is 2-3 timing valve 1
Since no pressure is generated in the chamber 13d of 3, the spool 13
b is moved to the right half position in the figure by the spring 13C, and the oil passage 65
is connected to the drain port 13e, so the oil passage 67, oil passage 80, orifice 69, oil passage 65, and drain port) 1
It is extracted relatively slowly after passing through 3e.

Here, when the vehicle speed becomes low to a certain extent, the governor pressure applied from the governor pressure circuit 23 to the chamber 14d of the 3-2 timing valve 14 through the oil passage 66 is applied to the spool 14.
The spool 14b can be raised to the left half position in the figure against the spring 14C, and the spool 14b can be lowered to the right half position in the figure to open the oil passage 6.
Passes between 5 and 67.

In this case, the servo release pressure is removed relatively quickly through the oil passage 67.3-2, the timing valve 14, the oil passage 65, and the drain port 13e than when the vehicle speed is high.

As a result of the above action, the servo release pressure is removed at a slow speed determined by the orifice 69 when the vehicle speed is high, and relatively quickly when the vehicle speed is low.

Therefore, at high vehicle speeds, when the front clutch 104 is released, the band servo 106' (second brake 104')
The effect of 6) is delayed, allowing a longer neutral interval, during which the engine speed increases in proportion to the vehicle speed, making it possible to downshift from 3rd gear to 2nd gear with less shift shock. can.

In addition, at low vehicle speeds, the delay in the activation of the second brake 106 relative to the release of the front clutch 104 can be reduced, and this activation delay can be matched to the time required for the engine rotation to rise by an amount corresponding to the vehicle speed, so that the above-mentioned shift It is possible to reduce the shift shock when the gear is down.

In addition, the 3-2 downshift valve 5 decreases the vehicle speed,
Also when the governor pressure in chamber 5d decreases correspondingly,
When the throttle opening degree is increased, the same effect as described above occurs, and the automatic transmission can be caused to perform a similar downshift from the third speed to the second speed.

Next, when the vehicle speed further decreases, the governor pressure in the chamber 3e of the -2 shift valve 3 cannot resist the spring force of the spring 3d, and this spring causes the shift valve 3b to fall.

3C descends from the left half position to the right half position in the figure and opens the oil passage 3.
0 and 31, and also allows the oil passage 31 to communicate with the drain port 3t.

As a result, the line pressure that was being supplied to the servo apply chamber 106a' passes through the check valve 76 in the oil passage 42, and
The oil is extracted through the oil passage 31 and drain port) 3t, and the second brake 10 is released by releasing the band servo 106'.
6 is deactivated.

Thus, only the friction element brake clutch 105 is engaged, and the automatic transmission is downshifted from the second speed to the first speed.

After that, return manual valve 2 to N range, and
2b is drained, the line pressure that was being supplied to the rear clutch 105 is reduced to the oil passage 29 and the check valve 7.
7. The oil passes through the oil passage 22 and is extracted from the port 2b of the manual valve 2, and the automatic transmission is in a neutral state where all friction is inactive and no power is transmitted.

While driving in the third gear, when the accelerator pedal is fully depressed to create a kick-down state, the plunger 8d of the throttle valve 8 is pushed to the right in the figure to its limit as described above, and kick-down pressure is applied to the circuit 24. (line pressure) is output.

This kickdown pressure is supplied to the port 3H of the 1-2 shift valve 3 on the one hand, and to the chamber 4p of the 2-3 shift valve 4 on the other hand through the oil passage 37, respectively.

The kickdown pressure supplied to the chamber 4p acts on both the upper and lower pressure receiving surfaces of the land 4g of the spool 4b located in the left half position in the figure, and the upper pressure receiving surface of the land 4h, and in cooperation with the spring 4d, the spool Push down 4b and 4C to the right half position in the figure.

As a result, the 2-3 shift valve 4 downshifts the automatic transmission from the third speed to the second speed in the same manner as described above.

Moreover, when the vehicle speed further decreases, the kickdown pressure supplied from the circuit 24 to the port 3u of the 1-2 shift valve 3 becomes
It acts on the upper pressure receiving surface of the land 3h, the upper and lower pressure receiving surfaces of the land 3g, and the lower pressure receiving area difference of the land 3f, and works together with the spring 3d to move the spools 3b and 3C against the governor pressure in the chamber 3e. Push down from the left half position to the right half position.

As a result, the 1-2 shift valve 3 shifts down the automatic transmission from the second speed to the first speed in the same manner as described above.

゛When the kickdown state occurs while driving in 1st gear, the line pressure output to the circuit 25 as described above is applied to the land 3 of the spool 3C located in the right half position of the 1-2 shift valve 3 in the figure.
In addition to acting on the pressure receiving area difference between m and 3n, 2-
3 Spool 4b located in the right half position of shift valve 4 in the figure
land 4h.

It acts on the difference in pressure receiving area between the spools 41 and pushes each spool downward.

Also, the kickdown pressure of the circuit 24 is the 1-2 shift valve 3.
Lands 3g, 3 of spool 3b located in the right half position in the figure.
It acts on the difference in pressure receiving area between 2-3 shift valves 4 and the land 4g of the spool 4b located in the right half position in the figure of the 2-3 shift valve 4, pushing each spool downward.

In addition, the spools of both shift valves 3 and 4 are each
A downward force due to d and 4d is working.

Governor pressure acts on the spools of the shift valves 3 and 4 in the chambers 3e and 4e to oppose the above downward force, and the vehicle speed is such that the governor pressure overcomes the downward force applied to the spools of the 1-2 shift valves. , the 1-2 shift valve 3 shifts up from 1st gear to 2nd gear as described above, and the vehicle speed is such that the governor pressure overcomes the downward force applied to the spool of the 2-3 shift valve 4. To become and,
As described above, the 2-3 shift valve 4 can shift up from the second speed to the third speed.

However, as is clear from the above, the downward force applied to the spools of both shift valves 3 and 4 is larger than the downward force at the normal throttle opening, so the You can accelerate without upshifting using the large driving force of low gears.

Next, the operation when the II range is selected while the vehicle is running in the third speed with the manual valve 2 set to the D range will be described.

While driving in the third speed with the D range set, the line pressure led to the oil passage 40 passes through the groove 6e and the oil passage 6g and reaches the chamber 6f, moving the spool 6b from the upper half position in the figure to the lower half position. This spool position is then maintained by line pressure from the oil passage 31.41 through the groove 6e and the oil passage 6g to the chamber 6f.

Now, if you switch manual valve 2 to II range,
'The line pressure circuit 16 is connected to the ports 2b and 2C, and the line pressure reaches the same location as described above from the port 2b, and from the port 1-2C, the oil passage 35, the shift valve 34, and the oil passage 33 are connected. After that, it reaches the chamber 4C of the 2-3 shift valve 4,
It acts on the land 4m to push down the spool 4C from the left half position in the figure to the right half position, and is then supplied to the oil path 45.

Therefore, the 2-3 shift valve 4 is in the same downshift state as described above, and the automatic transmission is shifted to the front clutch 10.
4 and the pressure supplied to the servo release chamber 106b' is removed to shift down from the third speed to the second speed, and the spool 4C is held in the lowered position by the line pressure supplied to the chamber 4C. Therefore, even if the vehicle speed increases, the gear will not be shifted up to third gear.

Since the line pressure booster valve 6 is in the above state, the line pressure guided to the oil passage 45 is guided to the port 7h of the pressure modifier valve 7 via the oil passage 43 and the shuttle valve 46.

Thus, the pressure modifier valve 7 outputs the pressure modifier pressure of the pressure modulation upper limit value (see FIG. 3 e-f) during all throttle openings to the oil passage 54 by the above-mentioned pressure regulating action, and the pressure modifier pressure is Valve 1 is supplied with this pressure modifier pressure.

As a result, the regulator valve 1 generates a line pressure corresponding to the upper limit value of the pressure regulation in the line pressure circuit 16 over all throttle openings by the above-described action.

Therefore, even at small or medium throttle openings, a sufficiently high line pressure can be obtained to strongly operate the rear clutch 105 and band servo 106', ensuring sufficient engine braking effectiveness in the II range. can.

When the vehicle speed decreases to a value while driving in the above II range, the spools 3b and 3C of the 1-2 shift valve 3 are lowered from the left half position to the right half position in the figure by the spring 3d. In the same manner as above, the automatic transmission is downshifted from second gear to first gear.

At this time, there is no oil pressure in the oil passage 31, and as a result, the spool 6b of the line pressure booster valve 6 loses the force that holds it in the rightward position in the lower half of the figure, and the spring 6 moves to the position shown in the upper half.
Returned with C.

As a result, the line pressure of the oil passage 45 comes to a dead end at the line pressure booster valve 6, and the oil passage 43 communicates with the drain port 9C of the throttle failsafe valve 9 via the oil passages 44 and 47.

Thus, the pressure modifier valve 7) 7
h is connected to the circuit 48 by the switching operation of the shuttle valve 46.
The pressure modifier valve 7 supplies the pressure modifier pressure to the regulator valve 1 through the oil passage 54 as described above, and the line pressure as described above is supplied to the regulator valve 1 through the circuit 16. It is possible to create functions within the body.

Thereafter, when the vehicle speed increases and the shift valve enters the upshift state due to the governor pressure in the chamber 3e of the ■-2 shift valve 3, the automatic transmission shifts from the first gear to the second gear as described above. Will be uploaded.

However, at this time, the line pressure generated in the oil passage 31
1 to the line pressure booster valve 6, the spool 6b of this valve located in the upper half of the figure no longer moves to the right.

Therefore, the line pressure booster valve 6 is used only when driving in 3rd gear and switching to II range to shift to 2nd gear, or when selecting I range from 3rd gear to shift to 2nd gear as described below. By keeping the line pressure at a constant high value over all throttle openings, as shown in the figure, the necessary capacity is secured when the second brake grips the clutch drum, and the effectiveness of the engine brake is ensured when the II range is set. , 1st
Once the speed is reached, the line pressure will not be boosted even if you repeatedly shift up from 1st gear to 2nd gear and downshift from 2nd gear to 1st gear, and the shift shock will not become large. .

In addition, when changing from 2nd speed of D range to II range,
Since the second brake grips the clutch drum in advance, its capacity is smaller than that when selecting from the third gear to the II range or range range even during engine braking, and there is no need to increase the line pressure with a line pressure booster valve.

Next, when the manual valve 2 is set to the ■ range, the line pressure circuit 16 communicates with the ports 2b and 2c as well as the port 2d.

The line pressure reaches the same locations as described above from ports 2b and 2C, and is supplied to the first speed fixed range pressure reducing valve 11 from port 2d.

Since there is no initial pressure in the chamber 11d, the pressure reducing valve 11 is pushed down to the right half position in the figure by the spool 11C, but the line pressure from the oil passage 59 reaches the chamber 11d from the oil passage 58. By pushing up the spool 11b and draining part of the line pressure from the drain port Ilf, it is balanced at the left half position in the figure, and the pressure is reduced to a magnitude equal to the spring force of the spring 11C at this position.

Therefore, the line pressure led to the oil passage 59 is reduced to a certain level, and the oil passage 58, the shuttle valve 28, the oil passage 2
6, spool land 31 of 1-2 shift valve 3
and exerts a downward force on spool 3C.

At high vehicle speeds, where the upward force due to the governor pressure in the chamber 3e is greater than this downward force, the spools 3b and 3C are placed in the left half position in the figure, and the shift valve 3 maintains the automatic transmission in the second gear state. , engine overrun can be prevented when the I range is selected while driving at high speed.

In this case, the line pressure is increased by the line pressure booster valve 6 in the II range only when selecting the ■range from the third speed and changing to the second speed.

When the vehicle speed decreases and the upward force due to the governor pressure in the chamber 3e decreases, the spool 3C is lowered to the right half position in the figure by the downward force due to the constant depressurizing oil acting on the spool land 31, and the spool 3b is lowered. , this lower end surface and land 3h
Due to the upward force caused by the constant pressure oil acting on the spring 3
In the state where d is contracted, it is held in the left half position in the figure and separated from the spool 3C.

At this time, the oil passage 27 that was communicating with the drain port 3S is communicated with the oil passage 26, and a certain amount of reduced pressure oil in the oil passage 26 is supplied to the low reverse brake 107 via the oil passage 27, and the operation of this brake is controlled. By keeping the clutch 105 engaged, the single-dynamic transmission can run the vehicle while applying engine braking in the ■ range.

Note that the first speed fixed range pressure reducing valve 11 reduces the line pressure from the oil passage 59 to a constant value determined by the spring 11C, and then returns the line pressure to the oil passage 59.
8, the shift point of the 1-2 shift valve 3 in the first speed fixed range can be set to a desired constant vehicle speed, and engine overrun can be prevented without delay at any throttle opening.

When manual valve 2 is changed from N range to N range,
The line pressure circuit 16 communicates only with the port 2a.

The line pressure passes through the oil passage 60 from the port 2a, and on the other hand, passes through the shuttle valve 28 and the oil passage 26 to reach the 1-2 shift valve 3. At this time, since governor pressure is generated only during forward movement, the governor pressure is in the chamber 3e. Since the spools 3b and 3C are always in the right half position in the figure, the low
The oil is supplied to the reverse brake 107 and the front clutch 104 via the orifice 78, the shuttle valve 61, and the oil passage 62.

The line pressure toward the front clutch 104 is throttled midway through the orifice 78, and is initially low and then gradually rises.

This front clutch supply pressure branches from the middle of the oil passage 60 and reaches the accumulator chamber 12a, and the stepped piston 1
2b is pushed down against the spring 12f.

As a result, the front clutch supply pressure is slowly increased, and the front clutch 104 is slowly engaged without causing a select shock when the manual valve 2 is changed from the N range to the N range.

Thus, the automatic transmission requires engagement of the front clutch 104,
Activation of the low reverse brake 107 makes it possible to travel backwards.

When manual valve 2 is returned to the N range, port 2
a is connected to the drain, and the line pressure in the front clutch 104 is quickly extracted through the oil passage 62, the shuttle valve 61, the oil passage 60, the check valve 79, and the port 2a of the manual valve 2, and the low reverse brake 107
The line pressure inside is also oil passages 27, 26, shuttle valve 28,
The oil is quickly extracted through the oil passage 60 and the port 1-2a of the manual valve 2, and the automatic transmission is placed in a neutral state.

Thus, as is clear from the above description of the operation, the automatic transmission equipped with the shift point control device of the present invention shifts the upshift (from 2nd gear to 3rd gear) shift point during partial to lands 4h and 4i. The desired value can be set by adjusting the area difference, that is, the pressure-receiving area of the land 41, and the downshift (from 3rd gear to 2nd gear) shift point in partial mode can be set to the desired value by adjusting the operating characteristics of the 3-2 downshift valve 5. Also, the upshift (from 2nd to 3rd gear) shift point during kickdown can be determined as desired by the pressure receiving area of the land 4g, and the downshift (from 3rd to 3rd gear) during kickdown can be determined as desired by the pressure receiving area of the 4g land. Since the shift point (to 2nd gear) can be determined as desired by the pressure-receiving area of land 4h, the determining factors for upshift and downshift shift points can be set independently for both partial and kickdown, allowing ideal shifting. A pattern is obtained.

[Brief explanation of the drawing]

FIG. 1 is a schematic system diagram illustrating a power transmission train of an automatic transmission, and FIG. 2 is a hydraulic circuit diagram showing the transmission control circuit provided with the device of the present invention. 1...Regulator valve, 2...Manual valve, 3...1-2 shift valve, 4...2-3 shift valve, 5...3-2 down shift valve, 6...
・Line pressure booster valve, 7... Pressure booster valve, 8... Throttle valve, 9...
・Throttle fail-safe valve, 10... Throttle modulator valve, 11... 1st speed fixed range pressure reducing valve, 12... Accumulator, 13... 2-
3 timing valve, 14...3-2 timing valve, 15...front clutch pressure reducing valve, 16...
・Line pressure circuit, 20...Oil cooler, 21...
Various lubricating parts, 25...speed change control pressure circuit, 28. 34
．． 46.61...Shuttle valve, 48...Throttle pressure circuit, 68,76.77.79...Check valve, 69.73,74,75.78...Orifice, 100...Crank shirt 1-1101...Torque converter, 102...Main shaft, 103
...One-way clutch, 104...Front clutch, 105...Rear clutch, 106...Second brake, 107...Low and reverse brake, 108...One-way clutch, 109...
・Intermediate shaft, 110...first planetary gear group, 111
...Second planetary gear group, 112...Output shaft, 113...First governor valve, 114...Second governor valve.

Claims (1)

[Claims] 1. Upshifting in response to governor pressure corresponding to vehicle speed;
In an automatic transmission equipped with a shift valve that supplies or removes working pressure oil from a corresponding friction element by downshifting, the spool of the shift valve is divided into two in its axial direction so that the governor pressure acts on the spool. One spool is used for switching the oil path of the working oil pressure, and the other spool is used for control, and this control spool has a pressure receiving surface that receives oil pressure related to the throttle opening and a pressure receiving surface that receives kickdown pressure at the downshift position. and a pressure receiving surface that receives the kickdown pressure at the upshift position, while facing the governor pressure and the hydraulic pressure related to the spring and the throttle opening separately from the shift valve. a downshift valve that supplies hydraulic pressure to the spool split end face of the shift valve and presses the oil path switching spool to a downshift position when the spool is displaced due to governor pressure;
A shift point control device for an automatic transmission, wherein the shift points for upshift and downshift during partial and upshift and downshift during kickdown can be set independently. 2. The downshift valve applies hydraulic pressure related to the throttle opening to a step area formed on the spool, and when the spool is displaced against the governor pressure, the downshift valve applies the hydraulic pressure related to the throttle opening to the divided end surface of the spool of the shift valve. 2. A shift point control device for an automatic transmission according to claim 1, wherein said shift point control device is adapted to operate. 3 Shifts up in response to governor pressure corresponding to vehicle speed,
In an automatic transmission equipped with a shift valve that supplies or removes working pressure oil from a corresponding friction element by downshifting, the spool of the shift valve is divided into two in its axial direction so that the governor pressure acts on the spool. One spool is used for switching the hydraulic oil path, and the other spool is used for control, and this control spool has a pressure receiving surface that receives oil pressure related to the throttle opening and a pressure receiving surface that receives kickdown pressure at its downshift position. Three pressure receiving surfaces are formed: a pressure receiving surface and a pressure receiving surface receiving the kickdown pressure at the upshift position, and the governor pressure and the hydraulic pressure related to the spring and the throttle opening are opposed to each other separately from the shift valve. A downshift valve is provided that applies hydraulic pressure to the spool split end face of the shift valve to press the oil path switching spool to a downshift position when the spool is displaced due to governor pressure. ,
This makes it possible to independently set the shift points for upshift and downshift during partial and upshift and downshift during kickdown, and furthermore, in the fixed forward gear range, the related hydraulic pressure is transferred to the spool of the shift valve. A shift point control device for an automatic transmission, characterized in that the shift point control device for an automatic transmission is configured to act on a divided end face to press the oil passage switching spool to a downshift position. 4. The downshift valve applies hydraulic pressure related to the throttle opening to a stepped area formed on the spool, and when the spool is displaced against governor pressure, the downshift valve applies hydraulic pressure related to the throttle opening to the divided end surface of the spool of the shift valve. 4. The shift point control device for an automatic transmission according to claim 3, wherein